The present invention relates generally to friction stir welded assemblies and in particular to repairs for friction stir welded assemblies.
Friction stir welding is often employed to joint metal workpieces together where it is desirable to retain the original metal characteristics after the joining process is complete. This is possible because the material is not melted during the friction stir welding process and usually no filler material is used. During this welding process a probe is rotated while being moved along a joint line. The frictional heat causes the affected material to soften, but not melt. This area of deformed material is called the stir zone.
Friction stir welding operations are often conducted in a highly repetitive operation and, unfortunately, sometimes problems or variations occur in the control or execution of the process and discrepant welds are produced. Scrapping the workpieces with the discrepant welds is undesirable for cost reasons. However, the welded assembly cannot be used unless the joint strength meets the requirements for the particular assembly.